Effects of Prereactivation Propranolol on Cocaine Craving Elicited by Imagery Script/Cue Sets in Opioid-dependent Polydrug Users: A Randomized Study

Approaches to studying emotion using physiological responses to spoken narratives: A scoping review

Narratives are effective tools for evoking emotions, and physiological measurements provide a means of objectively assessing emotional reactions - making them a potentially powerful pair of tools for studying emotional processes. However, extent research combining emotional narratives and physiological measurement varies widely in design and application, making it challenging to identify previous work, consolidate findings, and design effective experiments. Our scoping review explores the use of auditory emotional narratives and physiological measures in research, examining paradigms, study populations, and represented emotions. Following the PRISMA-ScR Checklist, we searched five databases for peer-reviewed experimental studies that used spoken narratives to induce emotion and reported autonomic physiological measures. Among 3466 titles screened and 653 articles reviewed, 110 studies were included. Our exploration revealed a variety of applications and experimental paradigms; emotional narratives paired with physiological measures have been used to study diverse topics and populations, including neurotypical and clinical groups. Although incomparable designs and sometimes contradictory results precluded general recommendations as regards which physiological measures to use when designing new studies, as a whole, the body of work suggests that these tools can be valuable to study emotions. Our review offers an overview of research employing narratives and physiological measures for emotion study, and highlights weaknesses in reporting practices and gaps in our knowledge concerning the robustness and specificity of physiological measures as indices of emotion. We discuss study design considerations and transparent reporting, to facilitate future using emotional narratives and physiological measures in studying emotions.

New Approaches for Alcohol Use Disorder Treatment via Memory Retrieval and Reconsolidation Manipulations

Relapse to alcohol seeking and drinking is a major clinical challenge in alcohol use disorder and is frequently brought about by cue-induced craving, caused by exposure to cues that evoke alcohol-related memories. It has been postulated that memories become labile for manipulation shortly after their retrieval and then restabilize in a "memory reconsolidation" process. Disruption or interference with the reconsolidation of drug-associated memories has been suggested as a possible strategy to reduce or even prevent cue-induced craving and relapse. Here, we review literature demonstrating the capacity of behavioral or pharmacological manipulations to reduce relapse in animal models and humans when applied after a short retrieval of memories associated with alcohol, suggestively disrupting the reconsolidation of such memories. We suggest that while there is a clear potential of using post-retrieval manipulations to target specific relapse-evoking memories, future research should be more systematic, standardized, and translational. Specifically, we discuss several critical limitations and boundary conditions, which should be addressed to improve consistency and replicability in the field and lead to the development of an efficient reconsolidation-based relapse prevention therapy.

Pharmacological Treatments for Cocaine Craving: What Is the Way Forward? A Systematic Review

BACKGROUND

cocaine craving is a core feature of cocaine use disorder and remains a critical challenge for abstinence and relapse prevention. This review summarizes the anti-craving efficacy of pharmacotherapies tested for cocaine use disorder, in the context of randomized-controlled clinical trials.

OBJECTIVES

we assessed the databases of the U.S. National Library of Medicine, Google Scholar, and PsycINFO, without date restrictions up to August 2022, to identify relevant studies.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS

we included double-blinded randomized-controlled trials investigating pharmacotherapies for cocaine craving and/or cocaine use disorder whose outcomes included cocaine craving.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two authors screened studies' titles and abstracts for inclusion, and both read all the included studies. We systematically gathered information on the following aspects of each study: title; author(s); year of publication; sample size; mean age; sample characteristics; study set-ting; whether participants were treatment-seeking; study design; craving measures; study interventions; drop-out rates; and other relevant outcomes.

RESULTS

Overall, we appraised 130 clinical trials, including 8137 participants. We further considered the drugs from the studies that scored equal to or greater than six points in the quality assessment. There was a correlation between craving and cocaine use outcomes (self-reports, timeline follow-back or urinary benzoylecgonine) in the vast majority of studies. In the short-term treatment, acute phenylalanine-tyrosine depletion, clonidine, fenfluramine, meta-chlorophenylpiperazine (m-CPP) and mecamylamine presented promising effects. In the long term, amphetamine, biperiden, carbamazepine, lisdexamfetamine, lorcaserin, methamphetamine, mirtazapine, pioglitazone, progesterone, guanfacine, levodopa, nefazodone presented promising anti-craving effects. Unfortunately, the highly tested medications were not successful in most of the trials, as follows: propranolol in the short term; amantadine, aripiprazole, bromocriptine, citicoline, ketamine, modafinil, olanzapine, topiramate in the long term. The remaining 52 medications had no positive anti-craving outcomes.

LIMITATIONS

Our review was limited by high heterogeneity of craving assessments across the studies and by a great range of pharmacotherapies. Further, the majority of the studies considered abstinence and retention in treatment as the main outcomes, whereas craving was a secondary outcome and some of the studies evaluated patients with cocaine use disorder with comorbidities such as opioid or alcohol use disorder, schizophrenia, bipolar disorder or attention deficit hyperactivity. Lastly, most of the studies also included non-pharmacological treatments, such as counseling or psychotherapy.

CONCLUSIONS

There is a direct association between craving and cocaine use, underscoring craving as an important treatment target for promoting abstinence among persons with cocaine use disorder. Clonidine, fenfluramine and m-CPP showed to be promising medications for cocaine craving in the short-term treatment, and amphetamine, biperiden, carbamazepine, lisdexamfetamine, lorcaserin, methamphetamine, mirtazapine, pioglitazone, progesterone, guanfacine, levodopa, nefazodone in the long-term treatment.

Impairing memory reconsolidation with propranolol in healthy and clinical samples: a meta-analysis

BACKGROUND

Reconsolidation impairment using propranolol is a novel intervention for mental disorders with an emotional memory at their core. In this systematic review and meta-analysis, we examined the evidence for this intervention in healthy and clinical adult samples.

METHODS

We searched 8 databases for randomized, double-blind studies that involved at least 1 propranolol group and 1 placebo group. We conducted a meta-analysis of 14 studies (n = 478) in healthy adults and 12 studies in clinical samples (n = 446).

RESULTS

Compared to placebo, reconsolidation impairment under propranolol resulted in reduced recall of aversive material and cue-elicited conditioned emotional responses in healthy adults, as evidenced by an effect size (Hedges g) of -0.51 (p = 0.002, 2-tailed). Moreover, compared to placebo, reconsolidation impairment under propranolol alleviated psychiatric symptoms and reduced cue-elicited reactivity in clinical samples with posttraumatic stress disorder, addiction or phobia (g = -0.42, p = 0.010).

LIMITATIONS

Methodological differences between studies posed an obstacle for identifying sources of heterogeneity.

CONCLUSION

Reconsolidation impairment is a robust, well-replicated phenomenon in humans. Its clinical use is promising and deserves further controlled investigation.

Neural substrates of propranolol-induced impairments in the reconsolidation of nicotine-associated memories in smokers

The majority of smokers relapse even after successfully quitting because of the craving to smoking after unexpectedly re-exposed to smoking-related cues. This conditioned craving is mediated by reward memories that are frequently experienced and stubbornly resistant to treatment. Reconsolidation theory posits that well-consolidated memories are destabilized after retrieval, and this process renders memories labile and vulnerable to amnestic intervention. This study tests the retrieval reconsolidation procedure to decrease nicotine craving among people who smoke. In this study, 52 male smokers received a single dose of propranolol (n = 27) or placebo (n = 25) before the reactivation of nicotine-associated memories to impair the reconsolidation process. Craving for smoking and neural activity in response to smoking-related cues served as primary outcomes. Functional magnetic resonance imaging was performed during the memory reconsolidation process. The disruption of reconsolidation by propranolol decreased craving for smoking. Reactivity of the postcentral gyrus in response to smoking-related cues also decreased in the propranolol group after the reconsolidation manipulation. Functional connectivity between the hippocampus and striatum was higher during memory reconsolidation in the propranolol group. Furthermore, the increase in coupling between the hippocampus and striatum positively correlated with the decrease in craving after the reconsolidation manipulation in the propranolol group. Propranolol administration before memory reactivation disrupted the reconsolidation of smoking-related memories in smokers by mediating brain regions that are involved in memory and reward processing. These findings demonstrate the noradrenergic regulation of memory reconsolidation in humans and suggest that adjunct propranolol administration can facilitate the treatment of nicotine dependence. The present study was pre-registered at ClinicalTrials.gov (registration no. ChiCTR1900024412).

Targeting the Reconsolidation of Licit Drug Memories to Prevent Relapse: Focus on Alcohol and Nicotine

Alcohol and nicotine are widely abused legal substances worldwide. Relapse to alcohol or tobacco seeking and consumption after abstinence is a major clinical challenge, and is often evoked by cue-induced craving. Therefore, disruption of the memory for the cue–drug association is expected to suppress relapse. Memories have been postulated to become labile shortly after their retrieval, during a “memory reconsolidation” process. Interference with the reconsolidation of drug-associated memories has been suggested as a possible strategy to reduce or even prevent cue-induced craving and relapse. Here, we surveyed the growing body of studies in animal models and in humans assessing the effectiveness of pharmacological or behavioral manipulations in reducing relapse by interfering with the reconsolidation of alcohol and nicotine/tobacco memories. Our review points to the potential of targeting the reconsolidation of these memories as a strategy to suppress relapse to alcohol drinking and tobacco smoking. However, we discuss several critical limitations and boundary conditions, which should be considered to improve the consistency and replicability in the field, and for development of an efficient reconsolidation-based relapse-prevention therapy.

Are animal models of addiction useful?

BACKGROUND

Pre-clinical research involving non-human animals has made important contributions to our understanding of risk factors for addiction, neuroadaptations that follow chronic drug exposure and to the development of some efficacious pharmacotherapies for addiction. Despite these contributions, we argue that animal models of addiction have impeded progress in our understanding of addiction and its treatment in humans.

ARGUMENT

First, the majority of pharmacological treatments that were initially developed using animal models have failed to prove effective for the treatment of addiction in humans, resulting in a huge waste of resources. Secondly, we demonstrate that prevailing animal models that portray addiction as a disorder of compulsion and habit cannot be reconciled with observations that psychoactive drug use in humans is a goal-directed operant behaviour that remains under the control of its consequences, even in people who are addicted. Thirdly, addiction may be a uniquely human phenomenon that is dependent on language, which necessarily limits the validity of animal models. Finally, we argue that addicted brains must be understood as one component of broader networks of symptoms and environmental and social factors that are impossible to model in laboratory animals.

CONCLUSIONS

A case can be made that animal models of addiction have not served us well in understanding and treating addiction in humans. It is important to reconsider some widely held beliefs about the nature of addictive behaviour in humans that have arisen from the zeal to translate observations of laboratory animals.

Silent synapses dictate cocaine memory destabilization and reconsolidation

Cocaine-associated memories are persistent, but, upon retrieval, become temporarily destabilized and vulnerable to disruptions, followed by reconsolidation. To explore the synaptic underpinnings for these memory dynamics, we studied AMPA receptor (AMPAR)-silent excitatory synapses, which are generated in the nucleus accumbens by cocaine self-administration, and subsequently mature after prolonged withdrawal by recruiting AMPARs, echoing acquisition and consolidation of cocaine memories. We show that, upon memory retrieval after prolonged withdrawal, the matured silent synapses become AMPAR-silent again, followed by re-maturation ~6 hr later, defining the onset and termination of a destabilization window of cocaine memories. These synaptic dynamics are controlled by Rac1, with decreased and increased Rac1 activities opening and closing, respectively, the silent synapse-mediated destabilization window. Preventing silent synapse re-maturation within the destabilization window decreases cue-induced cocaine seeking. Thus, cocaine-generated silent synapses constitute a discrete synaptic ensemble dictating the dynamics of cocaine-associated memories and can be targeted for memory disruption.

Counterconditioning following memory retrieval diminishes the reinstatement of appetitive memories in humans

Appetitive memories play a crucial role in learning and behavior, but under certain circumstances, such memories become maladaptive and play a vital role in addiction and other psychopathologies. Recent scientific research has demonstrated that memories can be modified following their reactivation through memory retrieval in a process termed memory reconsolidation. Several nonpharmacological behavioral manipulations yielded mixed results in their capacity to alter maladaptive memories in humans. Here, we aimed to translate the promising findings observed in rodents to humans. We constructed a novel three-day procedure using aversive counterconditioning to alter appetitive memories after short memory retrieval. On the first day, we used appetitive conditioning to form appetitive memories. On the second day, we retrieved these appetitive memories in one group (Retrieval group) but not in a second group. Subsequently, all participants underwent counterconditioning. On the third day, we attempted to reinstate the appetitive memories from day one. We observed a significant reduction in the reinstatement of the original appetitive memory when counterconditioning was induced following memory retrieval. Here, we provide a novel human paradigm that models several memory processes and demonstrate memory attenuation when counterconditioned after its retrieval. This paradigm can be used to study complex appetitive memory dynamics, e.g., memory reconsolidation and its underlying brain mechanisms.

Open-label dose-extending placebos for opioid use disorder: a protocol for a randomised controlled clinical trial with methadone treatment

INTRODUCTION

More than 2 million individuals in the USA have an opioid use disorder (OUD). Methadone maintenance treatment is the gold standard of medication-based treatment for OUD, but high-dose methadone is associated with cardiotoxicity and respiratory complications, among other side effects. These adverse effects make enhancing the effectiveness of lower doses of methadone an attractive therapeutic goal. Long recognised for its capacity to enhance treatment outcomes for a wide range of neuropsychiatric disorders including pain, the placebo effect offers an as-yet untested avenue to such an enhancement. This approach is particularly compelling given that individuals with substance use disorder tend to have higher salience attribution and may thereby be more sensitive to placebo effects. Our study combines two promising clinical methodologies-conditioning/dose-extension and open-label placebo-to investigate whether placebo effects can increase the effective potency of methadone in treatment-seeking OUD patients.

METHODS AND ANALYSIS

A total of 120 newly enrolled treatment-seeking OUD patients will be randomly assigned to one of two different groups: either methadone plus daily placebo dose-extension (PDE; treatment group) or methadone/treatment as usual (control). Participants will meet with study team members five times over the course of 3 months of treatment with methadone (baseline, 2 weeks, and 1, 2 and 3 months postbaseline). Throughout this study time period, methadone dosages will be adjusted by an addiction clinician blind to patient assignment, per standard clinical methods. The primary outcome is methadone dose at 3 months. Secondary outcomes include self-report of drug use; 3-month urine toxicology screen results; and treatment retention. Exploratory outcomes include several environmental as well as personality factors associated with OUD and with propensity to demonstrate a placebo effect.

ETHICS AND DISSEMINATION

Human subjects oversight for this study is provided by the University of Maryland, Baltimore and University of Maryland, College Park Institutional Review Boards. Additionally, the study protocol is reviewed annually by an independent Data and Safety Monitoring Board. Study results will be disseminated via research conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT02941809.

Modulation of naturalistic maladaptive memories using behavioural and pharmacological reconsolidation-interfering strategies: a systematic review and meta-analysis of clinical and 'sub-clinical' studies

BACKGROUND

Consolidated memories can undergo enduring modification through retrieval-dependent treatments that modulate reconsolidation. This represents a potentially transformative strategy for weakening or overwriting the maladaptive memories that underlie substance use and anxiety/trauma-related disorders. However, modulation of naturalistic maladaptive memories may be limited by 'boundary conditions' imposed on the reconsolidation process by the nature of these memories.

METHODS

We conducted a systematic review and meta-analyses of behavioural and pharmacological studies examining retrieval-dependent modulation of reward- and threat-related memories in (sub) clinical substance use and anxiety/trauma, respectively.

RESULTS

Of 4938 publications assessed for eligibility, 8 studies of substance use and 10 of anxiety (phobia)- and trauma-related symptoms were included in the meta-analyses. Overall, the findings were in the predicted direction, with most studies favouring the 'retrieval + treatment' condition. However, the magnitude of effects was dependent upon the nature of treatment, with pharmacological interventions showing a medium-sized effect (g = 0.59, p = 0.03) and behavioural treatments, a relatively small effect (g = 0.32, p = 0.10) in studies of phobia/trauma. Among studies of substance use, post-retrieval behavioural interventions yielded a larger effect (g = 0.60, p < 0.001) relative to pharmacological treatments (g = - 0.03, p = 0.91), with treatment type being a statistically significant moderator (χ2(1) = 4.20, p = 0.04).

CONCLUSION

Modification of naturalistic maladaptive memories during reconsolidation appears to be a viable treatment strategy for substance use and phobias/trauma disorders. However, high levels of heterogeneity and methodological variation limit the strength of conclusions that can be drawn from the reviewed studies at this stage.

Reconsolidation blockade for the treatment of addiction: challenges, new targets, and opportunities

Addiction is a chronic, relapsing disorder. The progression to pathological drug-seeking is thought to be driven by maladaptive learning processes which store and maintain associative memory, linking drug highs with cues and actions in the environment. These memories can encode Pavlovian associations which link predictive stimuli (e.g., people, places, and paraphernalia) with a hedonic drug high, as well as instrumental learning about the actions required to obtain drug-associated incentives. Learned memories are not permanent however, and much recent interest has been generated in exploiting the process of reconsolidation to erase or significantly weaken maladaptive memories to treat several mental health disorders, including addictions. Normally reconsolidation serves to update and maintain the adaptive relevance of memories, however administration of amnestic agents within the critical "reconsolidation window" can weaken or even erase maladaptive memories. Here we discuss recent advances in the field, including ongoing efforts to translate preclinical reconsolidation research in animal models into clinical practice.

Exacerbated Craving in the Presence of Stress and Drug Cues in Drug-Dependent Patients

In addiction, risk factors for craving and use include stress and drug-related cues. Stress and cues have additive or more-than-additive effects on drug seeking in laboratory animals, but, surprisingly, seem to compete with one another (ie, exert less-than-additive effects) in human laboratory studies of craving. We sought heretofore elusive evidence that human drug users could show additive (or more-than-additive) effects of stress and cues on craving, using ecological momentary assessment (EMA). Outpatients (N=182) maintained on daily buprenorphine or methadone provided self-reports of stress, craving, mood, and behavior on electronic diaries for up to 16 weeks. In three randomly prompted entries (RPs) per day, participants reported the severity of stress and craving and whether they had seen or been offered opioids, cocaine, cannabis, methamphetamine, alcohol, or tobacco. In random-effects models controlling for between-person differences, we tested effects of momentary drug-cue exposure and stress (and their interaction) on momentary ratings of cocaine and heroin craving. For cocaine craving, the Stress × Cue interaction term had a positive mean effect across participants (M=0.019; CL95 0.001-0.036), denoting a more-than-additive effect. For heroin, the mean was not significantly greater than 0, but the confidence interval was predominantly positive (M=0.019; CL95 -0.007-0.044), suggesting at least an additive effect. Heterogeneity was substantial; qualitatively, the Stress × Cue effect appeared additive for most participants, more than additive for a sizeable minority, and competitive in very few. In the field, unlike in human laboratory studies to date, craving for cocaine and heroin is greater with the combination of drug cues and stress than with either alone. For a substantial minority of users, the combined effect may be more than additive.

Selective Inhibition of Amygdala Neuronal Ensembles Encoding Nicotine-Associated Memories Inhibits Nicotine Preference and Relapse

BACKGROUND

Nicotine craving and relapse often occurs after reactivation of nicotine reward memories. We recently developed a memory retrieval-reconsolidation interference procedure in which reactivating nicotine reward memories by acute exposure to nicotine (the unconditioned stimulus [UCS]) and then pharmacologically interfering with memory reconsolidation decreased relapse to nicotine seeking in rats and nicotine craving in smokers. Here, we investigated underlying mechanisms.

METHODS

In the first series of experiments, we trained rats for nicotine-induced conditioned place preference (CPP) or nicotine self-administration and ventricularly microinjected them with the protein synthesis inhibitor anisomycin immediately after UCS-induced memory retrieval. In the second series of experiments, we used tyramide-amplified immunohistochemistry-fluorescence in situ hybridization to examine neural ensembles in the basolateral amygdala (BLA) reactivated by nicotine conditioned stimulus- or UCS-induced memory retrieval. We then used the Daun02 chemogenetic inactivation procedure to selectively inhibit the nicotine UCS-reactivated BLA neuronal ensembles.

RESULTS

Ventricular injections of the anisomycin immediately after nicotine UCS memory retrieval inhibited subsequent nicotine CPP and relapse to operant nicotine seeking after short or prolonged abstinence. More important, within BLA, distinct neuronal ensembles encoded pavlovian CPP and operant self-administration reward memories and nicotine (the UCS) injections in the home cage reactivated both neuronal ensembles. Daun02 chemogenetic inactivation of the nicotine-reactivated ensembles inhibited both nicotine CPP and relapse to nicotine seeking.

CONCLUSIONS

Results demonstrate that the nicotine UCS-induced memory retrieval manipulation reactivates multiple nicotine reward memories that are encoded by distinct BLA neuronal ensembles that play a role in nicotine preference and relapse.

Garcinol Blocks the Reconsolidation of Multiple Cocaine-Paired Cues after a Single Cocaine-Reactivation Session

Manipulations of memory reconsolidation can interfere with the ability of a drug-paired cue to drive drug-seeking behavior. However, the typical reconsolidation paradigm that reactivates the memory through the presentation of the cue (conditioned stimulus (CS)) only interferes with the memory of the reactivated CS while leaving other drug-paired CSs intact and able to continue driving drug-seeking behavior. Here, we used a novel unconditioned-stimulus (US) reactivation paradigm to interfere with the ability of multiple cues to drive drug-seeking behavior after just one reactivation and treatment session. Rats were trained to self-administer cocaine, during which time each active lever press resulted in an i.v. cocaine infusion paired with one of two cues that alternated within each session. The drug memory was later reactivated with either i.v. or i.p. cocaine presentation in the absence of any cue. The histone acetyltransferase (HAT) inhibitor garcinol or vehicle was injected following US reactivation to impair reconsolidation. Rats were later tested on cue-induced reinstatement to both cues. Garcinol administered after either i.v. or i.p. cocaine reactivation significantly decreased cue-induced reinstatement to both cues, indicative of reconsolidation impairment. In addition, garcinol administered in the absence of reconsolidation or at a 6 h delay when the memory should be restabilized had no effect on reinstatement, further suggesting that garcinol's effects on reinstatement are through reconsolidation-based mechanisms. Our results demonstrate that a US-reactivation paradigm may be preferable to traditional CS-reactivation paradigms for treating disorders that involve multiple CS-US associations and support investigations of garcinol as a therapeutic pharmacological agent.

Effect of Selective Inhibition of Reactivated Nicotine-Associated Memories With Propranolol on Nicotine Craving

IMPORTANCE

A relapse into nicotine addiction during abstinence often occurs after the reactivation of nicotine reward memories, either by acute exposure to nicotine (a smoking episode) or by smoking-associated conditioned stimuli (CS). Preclinical studies suggest that drug reward memories can undergo memory reconsolidation after being reactivated, during which they can be weakened or erased by pharmacological or behavioral manipulations. However, translational clinical studies using CS-induced memory retrieval-reconsolidation procedures to decrease drug craving reported inconsistent results.

OBJECTIVE

To develop and test an unconditioned stimulus (UCS)-induced retrieval-reconsolidation procedure to decrease nicotine craving among people who smoke.

DESIGN, SETTING, AND PARTICIPANTS

A translational rat study and human study in an academic outpatient medical center among 96 male smokers (aged 18- 45 years) to determine the association of propranolol administration within the time window of memory reconsolidation (after retrieval of the nicotine-associated memories by nicotine UCS exposure) with relapse to nicotine-conditioned place preference (CPP) and operant nicotine seeking in rats, and measures of preference to nicotine-associated CS and nicotine craving among people who smoke.

INTERVENTION

The study rats were injected noncontingently with the UCS (nicotine 0.15 mg/kg, subcutaneous) in their home cage, and the human study participants administered a dose of propranolol (40 mg, per os; Zhongnuo Pharma).

MAIN OUTCOMES AND MEASURES

Nicotine CPP and operant nicotine seeking in rats, and preference and craving ratings for newly learned and preexisting real-life nicotine-associated CS among people who smoke.

RESULTS

Sixty-nine male smokers completed the experiment and were included for statistical analysis: 24 in the group that received placebo plus 1 hour plus UCS, 23 who received propranolol plus 1 hour plus UCS, and 22 who received UCS plus 6 hours plus propranolol. In rat relapse models, propranolol injections administered immediately after nicotine UCS-induced memory retrieval inhibited subsequent nicotine CPP and operant nicotine seeking after short (CPP, d = 1.72, 95% CI, 0.63-2.77; operant seeking, d = 1.61, 95% CI, 0.59-2.60) or prolonged abstinence (CPP, d = 1.46, 95% CI, 0.42-2.47; operant seeking: d = 1.69, 95% CI, 0.66-2.69), as well as nicotine priming-induced reinstatement of nicotine CPP (d = 1.28, 95% CI, 0.27-2.26) and operant nicotine seeking (d = 1.61, 95% CI, 0.59-2.60) after extinction. Among the smokers, oral propranolol administered prior to nicotine UCS-induced memory retrieval decreased subsequent nicotine preference induced by newly learned nicotine CS (CS1, Cohen d = 0.61, 95% CI, 0.02-1.19 and CS2, d = 0.69, 95% CI, 0.10-1.28, respectively), preexisting nicotine CS (d = 0.57, 95% CI, -0.02 to 1.15), and nicotine priming (CS1, d = 0.82, 95% CI, 0.22-1.41 and CS2, d = 0.78, 95% CI, 0.18-1.37, respectively; preexisting nicotine CS, d = 0.92, 95% CI, 0.31-1.52), as well as nicotine craving induced by the preexisting nicotine CS (d = 0.64, 95% CI, 0.05-1.22), and nicotine priming (d = 1.15, 95% CI, 0.52-1.76).

CONCLUSIONS AND RELEVANCE

In rat-to-human translational study, a novel UCS-induced memory retrieval-reconsolidation interference procedure inhibited nicotine craving induced by exposure to diverse nicotine-associated CS and nicotine itself. This procedure should be studied further in clinical trials.

Reconsolidation and psychopathology: Moving towards reconsolidation-based treatments

Interfering with memory reconsolidation has valuable potential to be used as a treatment for maladaptive memories and psychiatric disorders. Numerous studies suggest that reconsolidation-based therapies may benefit psychiatric populations, but much remains unanswered. After reviewing the literature in clinical and healthy human populations, we discuss some of the major limitations to reconsolidation studies and clinical application. Finally, we provide recommendations for developing improved reconsolidation-based treatments, namely exploiting known boundary conditions and focusing on a novel unconditioned stimulus-retrieval paradigm.